Door-locking mechanism



March 1, 1927.

. F. G. CHAPIN DOOR LOCKING MECHANISM Filed may 5, 1926 2 Sheets-Sheet LIVER/TOE 0 N/E Y3 I 1;s1.9,5 6 March 1 1927. F. G. CHAHN i 9 noon LOCKING mscmmsm Filed May s. 1926.

2 Sheets-Shut 2 I F an on 6T Chap/Z7.

Br WM Patented Mar. 1, 1927.

FENTON G. CHAPIN, OF EAST ST. LOUIS, ILLINOIS.

DOOR-LOCKING MECHANISM.

Application filed May 5,

This invention relates to door locking mechanisms, and particularly to mechanisms of the type which comprise a means for preventing an elevator shaft door from being opened or closed unless the floorrof the elevator car is approximately level with the sill of the door opening.

One object of my invention is to provide an inexpensive elevator door locking mecha nism of the general type mentioned, that is easy to install, of simple design and of sulficiently rugged construction to insure its standing up successfully under the rough and constant usage to which such devices are subjected.

Another object is toprovide a door locking mechanism in which the door locking means is normally in an operative condition and is combined with an electrically-operated device that is adapted to be actuated to render said locking means inoperative, and thus permit the door to be opened.

Another object is to provide an automatic elevator door locking mechanism that can be changed easily so as to vary the time at which the door locking means becomes inoperative and operative when the car is approaching or leaving the floor or opening at which the door is locked.

Another object is to provide an electrically-operated door locking mechanism, which not only effectively prevents the door from being opened or closed unless the elevator car is in acertain approximate position with relation to the door opening, but

also prevents the car from being started unless the door is fully closed. Other objects and desirable features of my invention will be hereinafter pointed out.

I- have herein illustrated my invention embodied in a locking mechanism for a horizontally sliding elevator door, but I wish it to be understood that my invention is applicable to locking mechanisms for various other kinds of horizontally-sliding doors and also vertically sliding doors composed of one or a plurality of sections.

Figure 1 of the drawings is an elevational view of an elevator door locking mechanism constructed in accordance with my invention, showing the door partly open.

Figure 2 is an enlarged view of the door locking means and the electrically-operated device that holds said door locking means in an inoperative condition when theelevator 1926. Serial No. 106,835.

car occupies a certain approximate position with relation to the door opening, the cover plate of the housing that encases said parts being removed.

Figure 3 is an enlarged view, partly broken away, of the switch that controls said electrically-operated device. 1

Figure 4 is a view similar to Figure 2, showing the door locking means in its inoperative condition and the door released from same; and Figure 5 is a diagrammatic view, illustrating how the electrically-operated device and the two controlling switches are connected with each other.

Referring to the drawings which illustrate the preferred form of my invention, A designates an elevator car that operates in an elevator shaft, B designates a horizontally-sliding door that is used to close a door opening in said shaft, G designates a latch arranged in such a position that it will co-operate with 'amember D on the door to hold the doon in its closed position, E designates a locking device that is used to normally hold the latch G in such a position that the door cannot be disengaged from same, and F designates an electricallyoperated device that is used to render the locking device E inoperative.- The particular construction of the latch C, locking element E and electrically-operated device F are immaterial, but I prefer to use a reciprocating latch or latch of the plunger type that is normally held in position toco-operate with the member D on the door, either by gravity, or by a spring 1. The locking element E preferably consists of a lever or hinged dog pivotally connected at 2 to a supporting structure and arranged so that one end of same is normally engaged with a shoulder 3 on the latch C. The electrically-operated device F preferably consists of an electric magnet arranged so that when current passes through same it will move the lower end of the locking element E out of engagement with the shoulder 3 on the latch, and thus permit the latch C to move upwardly into an inoperative position when a cam 4 on the member D attached to the door strikes against a roller 5 on the lower end of the latch 0. Normally, the locking element E is held in engagement with the shoulder 3 on the latch by means of an expansion spring 6, as shown in Figure 2,,and

at such times it is impossible to open the door, due to the fact that the roller 5 on the latch is arranged in a notch 7 in the member D, and any lateral movement of the door in a direction to cause the cam a to move the latch upwardly is resisted by the locking element E which engages the latch. In order to facilitate the installation of the mechanism the latch C, locking element E and magnet F are arranged inside of a housing G that is adapted to be mounted inside of the elevator shaft at such a point that the latch C will engage the member D on the door when said door is moved into its closed position.

The magnet F is controlled by a switch H, preferably mounted on one of the guides or rails on which the elevator car travels, and provided with a movable switch member 8 that is combined with a spring 9 which normally holds said switch member in its open position, so as to maintain the magnet F in an inactive condition. In order that the door B may be opened, only when the floor of the car A is at approximately the same level as the sill of the door opening, said car is provided with a shoe I that is used to move the switch member 8 of the switch H into its closed position so --as to energize the magnet F. In the form of my invention herein illustrated the switch H is provided with a lever 10 that is equipped with a roller 11 which normally is arranged in the path of travel of the shoe I on the car A. When the car approaches the floor at which the door islocated, moving either upwardly or downwardly the shoe I on the car strikes against the roller 11 and moves the lever 10 inwardly, thereby causing said lever to engage a plunger 12 attached to the switch member 8 and move said switch member into its closed position. .So long as the car remains standing at the door opening, the magnet F will remain active, thereby holding the locking element E in an inoperative condition, as shown in Figure 4, and when the car moves away from the door opening, the switch member 8 of the switch H will move into its open position, thereby causing the lever 10 to swing outwardly so as to arrange the roller 11 thereon in a position to co-operate with the shoe I on the car the next time the car approaches the door opening. It is, of course, obvious that any suitable type or kind of switch can be used for controlling the electrically-operated device F, and that any suitable means can be used for actuating said switch so as to open andclose the circuit in which the device F is arranged, so long as the mechanism is constructed in such a way that the device F will be rendered active automatically when the car reaches a position with the floor of same approximately level with the sill of the door opening and will remain active so long as the car stays in that approximate position, thereby permitting the elevator door to be opened or closed at the will of the operator in charge of the car, during the time the car occupies such a position with relation to the door opening that passengers can enter or leave the car without danger of tripping or falling, as so often occurs when an elevator car is stopped at a position some distance above or some distance below the sill of the door opening. Due to the fact that the time at which the door locking means is rendered inoperative and is restored to its normal operative condition,

is governed by the shoe I on the car, it is possible with a door locking mechanism of the construction above described to vary the pointin the path of travel of the car at which the door can be opened by simply substituting a shoe I of different length. This is a very desirable characteristic of an elevator door locking mechanism, for in order to be commercially successful, such a mechanism should give the operatorsome leeway and not require the car to be stopped at a point with the floor of the car on the exact level of the sill of the door opening.

Another novel feature of my improved mechanism which adds greatly to its commercial utility is the fact that it is constructed in such a manner that the elevator car cannot be started unless the elevator door B is fully closed. This is accomplished bv arranging a switch K in the electric circuit that energizes the mechanism used to operate the car A and combining the movable member 7a of said switch with an actuating-lever 13 that is controlled or operated by the door or by a part attached to the door. In the form of my invention herein illustrated the switch K is ofthe plunger type and is provided with a spring 14. that constantly exerts pressure on the switch member 7a in a direction tending to move said switch member in a direction to open the circuit that energizes the operating mechanism of the elevator car. The switch K is arranged inside of the housing G, and the actuating lever l that is combined with said switch is provided with a roller 13 that projects outwardly through said housing at such a point that the cam d on the member D will engage said roller, and thus cause the lever 13 to hold the switch member 7:; in its closed position when the elevator door B is closed. When the elevator door is moved into its open position, as shown in Figure 4, the lever 13 swii'igs downwardly, thereby causing the switch K to open the circuit in which it is aranged. hen the elevator door is restored to its closed position, the cam l. on the member D moves the lever 13 upwardly, thus causing the circuit in which the switch K is arianged to he closed after the door has reached its fully closed position If desired, a signal L either of the visible or audible type,:can be arranged in the magnet circuit at such a point as to notify the operator in charge of the car when the door locking mechanism is in a condition to per-- connect the two switches H and K and the magnet F to the supply circuit. It is rugged enough to successfully stand up under constant usage and it can be changed easily to vary the point in the path of travel of the car at which the door B can be opened and closed by using a shoe I of different length. These features, coupled with the factthat the elevator door is normally locked in such a Way that it can not be opened either from the outside of the elevator shaft or from the inside of the shaft unless the floor of the elevator car is approximately level with the sill of the door opening, makes my mechanism a decided improvement upon the elevator door locking mechanisms now in general use.

As previously stated, my invention is not limited to a locking mechanism for elevator doors, but is applicable to locking mechanisms for various other types and kinds of sliding doors, and in most instances where the mechanism is used for locking doors other than elevator doors, the switch H will be manually controlled. For example, if the mechanism is used for locking. the door of a garage located at the rear of a dwelling, a manually-operable switch will be arranged in the dwelling so as'to enable the owner to control the door locking mechanism from the dwelling.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An elevator door locking mechanism, comprising a latch, a member on the door with which said latch co-operates, an element for locking said latch and holding it in locking engagement with its cooperating member on the door, an elecrtic magnet for rende'ing said locking element inoperative, a switch in the circuit that is used to energize said magnet, and a shoe on the elevator car arranged so as to close said switch and maintain it in its closed position when the floor of the car reaches and remains in a position approximately lever with the sill of the door openin 2. An elevator door locking mechanism,

comprising an automatically operating latch,

a member on the door that is adapted to be engaged by said latch when the door is moved into its closed position, a pivotal ly mounted locking element for said latch for preventing said latch from moving in a direction to releasethe door, a means that normally exerts pressure on said locking element in a direction to hold it in operative engagement with the latch, an electric anagnet for rendering said locking element in operative, a switch in the circuit that is used to energize said magnet, and a part on the elevator car arranged so as to close said switch and maintain it in its closed position when the elevator car is in proximity to the door opening.

3. An elevator door locking mechanism, comprising a member adapted to be attached to the elevator door and provided with a notch and a cam, a latch arranged in proximity to the door opening that is adapted to move automatically into the notch in said member when the door reaches its closed position, a locking element for holding the latch in engagement with the member on the door, an electric magnet for disengaging said locking element from said latch, a switch in the circuit that energizes said magnet, a part on the elevator car that opens and closes said switch, a second switch forming part of the mechanism for operating the car, and a controlling member for said second switch adapted to be operated by the cam on the member attached to the door.

4. A door locking mechanism, comprising a latch adapted to be mounted adjacent the door, a member on the door with which said latch co-operates, constructed so as to shift said latch into an inoperative position when the door is moved into its open position, a locking element, a spring for nor mally holding said locking element in a position where it prevents said latch from being rendered inoperative, an electric magnet for rendering said locking element inoperative, and a housing for closing said latch,

locking element and magnet.

5. An elevator door locking mechanism, comprising a spring-actuated door latch, a member on the door with which said latch co-operates, constructed so as to move said latch in opposition to its actuating spring when the door is moved into its open position, a pivotally-mounted locking element adapted to engage and hold said latch, a spring for normally maintaining said locking element in engagement with the latch, an electric magnet for disengaging the locking element from the latch, a switch in the circuit that is used to energize said magnet, and a shoe on the elevator car arranged so as to close said switch and maintain it in its closed position when the floor of the elevator car reaches and remains in a position approximately level with the sill of the door opening.

6. An elevator door locking mechanism, comprising a springactuated door latch, a member on the door with which said latch cooperates, constructed so as to more said latch in opposition to its actuating spring when the door is moved into its open position, a pivotally mounted locking element adapted to engage and hold said latch, a spring for normally maintaining said lockin'g element in engagement with the latch. an electric magnet for disengaging the locking element from the latch, a switch in the circuit that is used to energize said magnet, a second switch forming part of the mechanism for operating the car, and means operated by the movement of the elevator door for opening and closing said second switch.

7. An elevator door locking mechanism,

comprising a member ada ted to be attachedto the elevator door anc provided with a notch and with a cam, a spring-actuatedreciprocating latch arranged in proximity to the door and provided with a roller that is adapted to enter the notch in said member, a spring-actuated locking element that is normally arranged in engagement with a shoulder on said latch, an electric magnet for disengaging said locking element from said latch, a housing that encases said latch, look ing element and magnet, a, switch in the circuit that energizes said magnet, a shoe on the elevator car for opening and closing said switch, a second switch forming part of the mechanism for operating the car, and a cona trolling member for said second switch arranged 111 said houslng and provided with a part that is adapted to co-operate with the cam on the member attached to the door.

FENTQN G. CHAPIN. 

